<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>加加减减</title>
  <style>
    li{
      margin-bottom: 10px;
    }
  </style>
</head>

<body>

  <div id="app">
   <ul>
     <li v-for="(item,index) in list" :key="index">{{item}}
      <button @click="del(index)">删除</button>
     </li>
   </ul>
   <button @click="add">生成</button>
  </div>

  <script src="./vue.js"></script>
  <script>
  
    const app = new Vue({
      el: '#app',
      data: {
        list:[],
      },

      methods:{
       add(){
        this.list.push(Math.floor(Math.random() * 20))
       },
       del(index){
        this.list.splice(index,1)
       }
      }
    })
  </script>

</body>

</html>